Waterborne diseases are caused by pathogenic microorganisms e.g. bacteria, viruses, fungi or protists that are most commonly transmitted in contaminated fresh water. This is a prevalent problem in many developing countries due to poor sanitation and water/wastewater infrastructure as well as lack of suitable monitoring systems. The development of systems that provide a health warning to environmental agencies, NGOs or local communities requires the development of simple to use, fully integrated and relatively inexpensive biosensing platforms.

Science

We envisage a portable integrated sensing platform for rapid, on site, simultaneous detection of several contaminant species of bacteria associated with waterborne diseases. One possible route is the development of lab-on-a-chip device that measures the presence of DNA associated with key pathogens of concern (e.g. E. Coli, Salmonella and Pseudomonas Aeruginosas). Within this project we will focus on the design of arrays of DNA probes that capture different sections of the DNA characteristic of the pathogens of concern and measuring the hybridization events via amperometry, electrochemical impedance and quartz crystal microbalance technology. Redox-active sensitisers that bind with the hybrid duplex resulting from capture of target DNA will provide on-chip impedance signal amplification and enable more sensitive detection capability.

Impact

This approach will provide valuable information towards the design of a full lab-on-a-chip device with microfluidics, filtration, lysis and PCR. This novel approach offers a very timely and transformative solution to a complex problem requiring technology integration across a number of disciplines. The involvement of Public Health England as a stakeholder ensures a co-design approach for the development of fit-for-purpose devices.

As an example, seasonal high levels of pathogens are present in the Billings reservoir in Brazil, which provides water to half of the population of Sao Paulo city, putting at risk roughly 6.5 million people. The devices to be developed will enable early warning of high pathogen levels so that local authorities can take preventive actions. The platform can be adapted for on-site monitoring of different pathogens in most fresh water reservoirs.

The project will establish the underlying sensing technology for the first portable integrated sensing platform for rapid and on-site detection of several contaminants associated to waterborne diseases.

This is the PhD project of FRESH CDT student Josh Rainbow. He is supervised by Dr Pedro Estrela, Dr Niklaas Buurma from Cardiff University, Professor Nigel Silman from Public Health England and Dr Mirella Di Lorenzo.